In the Sea of Sand, why does Liang Wan have the same phoenix tattoo as Xiao Ge?

Xiao's tattoo is a unicorn, not quite the same as Liang Wan's, but both can be revealed depending on the temperature. There is no official response to this. But according to the flashbacks behind Shahai II, one of the Tibetans with Fatty also has a phoenix tattoo on his body, and can order the Wangs in this way. From this, we can know that Liang Wan must have a relationship with the Wang family.